A US woman who shot and killed her husband and two adult children before taking her own life is thought to have committed the shocking crime as a result of being ostracised from the religion she was raised in.

A federal judge sentenced a former Arkansas judge Wednesday to five years in prison — a stiffer punishment than prosecutors recommended — after he admitted giving young male defendants lighter sentences in return for personal benefits that included sexual favours.

Every time I tell a mate I’m doing a story on cryptocurrency, they invariably ask me the same two questions: should they invest their own hard-earned money, and which cryptocurrency will get them a Lamborghini/yacht/island quickest?

In a 60 Minutes online exclusive, reporter Liz Hayes quizzed Australian Prime Minister Malcolm Turnbull on his relationship with the unpredictable Twitter aficionado and US president Donald Trump ahead of their meeting at the White House Friday.

Man charged over trading takes own life

Sanjay Valvani, a hedge fund manager at Visium Asset Management LP who was arrested last week on insider trading charges, has been found dead after apparently taking his own life.

Valvani, 44, was discovered by his wife on Monday evening at his Brooklyn home with a wound to his neck, a New York Police Department spokeswoman said on Tuesday.

A suicide note and a knife were recovered, she added.

Valvani was arrested last Wednesday and accused of having fraudulently made $US25 million ($A33.56 million) by getting advanced information about US Food and Drug Administration approvals of generic drug applications.

Valvani pleaded not guilty to five counts including securities fraud, wire fraud and conspiracy and was freed on $US5 million bond secured by his home.

The death marked a stunning turn in one of the US government's biggest insider trading cases in years.

Valvani had been a partner at Visium Asset Management and was instrumental in building it with founder Jacob Gottlieb into an $US8 billion firm that counted some of the country's biggest pension funds as clients.